While appearing on CBS' "The Late Late Show With James Corden" on Monday, Cumberbatch was asked about how he keeps up with his muscular "Avengers" co-stars. The actor admitted that he doesn't try to maintain a muscular physique, but he had to go through a certain level of preparation for a shirtless scene in "Doctor Strange."

"I went really hard for it," he said.

Cumberbatch explained that he spent months "eating the right stuff" and working out. But when the day of the shoot came closer, he had to drastically change things up.

"The day and night before, you kind of dehydrate yourself and then on the actual day on set — I don't even know if I should be saying this — you basically are told told to eat Skittles and drink coffee because it dehydrates you," he said.

Cumberbatch described the preparation as "horrible," and said that "your skin then shrink wraps around the muscle fiber."

As a refresher, the "ubiquitous" scene that Cumberbatch is referring to happened approximately 40 minutes into the movie, after Strange left New York and traveled to Kamar-Taj.

After arriving there, Strange goes to a room to clean himself up. In the shirtless scene, he cuts his hair, trims his facial hair and looks at himself in the mirror to assess his new look when he's finished.

Strange seemed satisfied with his new look. Marvel/Disney

Appearing satisfied, he moves on to master the mystical arts in the remainder of the film.

Watch Cumberbatch explain his preparation for the shirtless scene below.

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